Regenerative stove.



A. C. NELSQN.

REGENERATIVE STOVE.

APPLICATION FILED IIov. Is. I9I5.

Patanted May 29, 1917.

4 SHEETSSHEET l.

SEcTwN GG mr Nmsms Fergus ca., fmmHJma, msnm: mn. n c.

A. C. NELSN.

REGENEBATIVE STVE.

APPLICATION FILED Nov. Ia, I9Is.

Patense May 29, 1917.

4 SHEETS-SHEET 4.

IINIIED STATES TENT FFIEL ALFRED C. NELSON, F LAKEWOOD, OHIO.`

REGENERATIVE STOVE.

Application led November 18, 1915.

To all LU/tom t may concern.'

Be it known that'I, ALFRED C. NELSON, a citizen of the United States, residing at Lakewood, in the county of Cuyahoga and State of Ohio, have invented certain new and useful Improvements in Regenerative Stoves, of which the following is a specifi tion.

This invention relates to regenerative stoves such as are used in connection with blast furnaces and known in the art as hot blast stoves. It may, however, be used in other forms of regenerative stoves, such, for instance, as those used in connection with open-hearth or crucible steel furnaces, glass furnaces or others where preheated air is used, In the construction of these stoves, bricks of refractory materials are eXtensively used. The principal object of my invention is to co-nstruct a hot blast stove of bricks of such forms and so laid that they expose to contact with the hot gases and air passing through the fines, more surface than is exposed by the bricks employed in previous constructions of hot blast stoves, and without sacrificing strength or simplicity of construction. In my improved construc tion, I accomplish thisobject by the use of bricks having wide bases and narrow tops, thus forming inclined sides so that when these bricks are laid, one on top of another the wall so formed has a saw tooth profile, exposing a large surface, but having downwardly facing shoulders so that dust will not collect on the sides of the brick.

To accomplish this, the principal object, I have devised special forms of bricks which, while differing from so called standard rectangular shapes, are still of such forms and I proportions that they can be readily manufactured at low cost, so that my improved hot blast stove can be built at practically the same cost as stoves using standard bricks and at less cost than those, in the construction of which, expensive special bricks enter largely.

A further object of my invention is to construct a hot blast stove in `which the major portion of the bricks that are employed are of the special shapes which I prefer to use, so that the number of different shapes required is a minimum.

A further object of my invention is to construct a stove in which the same style of bricks may be used for constructing the solid lining or outer wall next to the metal Specification of Letters Patent.

Patented May 29, 1917.

Serial No. 62,151.

shell as are used in forming the flues of the stove.

A further object of my invention is to construct the flues through which the hot gases and air to be` heated pass, in such a way that they presenta multiplicity of projections against which the gases or air impinge in vtheir passage through the iues and give up, or absorb heat, on account of such impingement, more rapidly than in'stoves in which the flue surfaces are smooth. By making the projections with gradually sloping faces on one side and abrupt faces on the other side, or, of saw tooth section, the How of hot gases may be directed against the gradually sloping faces which will not collect the dirt and soot which are carried by the hot gases. The air to be heated may be directed againstthe abrupt faces of the projections causing it to quickly absorb heat from the walls. The whirling motion imparted to the air passing` the projections will so diffuse the absorbed heat that the air will be uniformly heated.

A further object of my'invention is to provide suitable bricks of which a stove may be built to attain the foregoing and other objects of my invention.

In the construction of a hot blast stove according to my invention.` I employ, as fillers, rectangular prismoidal bricks, having both their sides. and their ends tapered to the same angle. Part of these bricks have their sides and their ends tapered from the wide to the narrow base, and others have their sides tapered from the wide to the narrow base, while their ends are tapered from the narrow to the wide base. For the stretchers I prefer to employ frusto-wedge shaped bricks, known in the art as arch bricks, although, as will be apparent from these specifications, the stretchers may be formed by laying end to end alternately the two styles of prismoidal bricks such as I employ as fillers. The reasons for the use of these special bricks and the manner of constructing my improved hot blast stove are disclosed in the accompanying drawings in which Figure l is a vertical section, on line I-I-I-I of Fig. 2, through a hot blast stove embodying my improvements.

Fig. 2 is a horizontal cross section on two planes, one-half of the figure being a section on line A-A, and the other half of the figurevbeing a section on line B-B of Fig. 1, thus showing in plan view, the method of laying consecutive layers of brick in `the building of a hot blast stove embodying my improvements.

Fig. 3 is a horizontal cross section, onehalf being taken on line D-D, and the other half on line C-C of Fig. 1.

Fig. 4 is a horizontal cross section, onehalf being taken on line E--E, and the other on line F-F of Fig. 1.

Fig. 5 is a vertical section taken on line G-Gr, Fig. 1.

Figs. 1 to 5 inclusive represent a side fired hot blast stove.

Fig. 6 is a horizontal section through a center fired hot blast stove, the section being taken on two planes, one-half of the view showing one layer of brick, and the other half showing the next lower or next higher layerof brick.

Fig. 7 is an enlarged perspective view of the checker-work showing three successive layers of brick, laid asthey are shown in Figs. 1 to 6 inclusive, the stretchers being of frusto-wedge shape and the fillers being of rectangularl prismoidal form having their sides tapered from the wide to the narrow base and their ends tapered from the narrow to the wide base at the same angles to the vertical as are the sides of the stretchers. The bricks employed for making the checker-work or flues in the construction of stoves shown in Figs. 1 to 7 inclusive, are shown in detail in Figs. 11 to 19 inclusive.

Fig. 8 is a fragmentary horizontal section drawn to an enlarged scale of a hot blast stove using bricks such as are shown in Figs. 11 to 19 inclusive, and shows the manner in which I employ my rectangular' prismoidal brick as fillers in the formation of the circular wall or lining which surrounds the checker-work, inside the metal shell of the stove.

Fig. 9 is a section on line M-M of Fig. 8, showing the manner of laying the fillers in alternate layers.

Fig. 10 is a section on line N-N of Fig. S.

Figs. 11, 12 and 13 are respectively plan, side and end views of one of my Vrectangular prismoidal brick in which both the sides andends are tapered in the same direction from the wide to the narrow base.

Figs. 14, 15 and 1G are respectively plan, side and end views of one of my rectangular prismoidal brick in which the sides are tapered from the wide to the narrow base, and the ends are tapered from the narrow to the wide base.

Figs. 17 18 and 19 are respectively plan, side and end views of one of my frustowedge shaped or arch brick having tapered sides and parallel ends at right angles to the bases.

In the figures thus far described, theflues or checkerwork and the outer wall or lining next to the metal shell are built of brick, all laid parallel to, or at right angles to a given vertical plane, this being in accordance with the teachings of my Patent No. 925,827 of June 22, 1909.

Fig. 20 is a horizontal cross section of a two pass center fired stove having its flues and checker-work formed of radial and circular walls. One-half of the view shows one layer, and the other half shows the next lower or next higher layer of brick.

Fig. 21 is a fragmentary enlargement of a portion of Fig. 20.

Fig. 22 is a horizontal section through a center red three pass Ystove having its fines and checker work formed of radial and circular walls. This view also shows two layers of brick, one-half showing one layer, and the other half showing the next lower or next higher layer.

Fig. 23 is a fragmentary enlargement of a portion of Fig. 22.

Fig. 24 is a plan view of a layer of brick checker-work made according to my invention, but composed of only one shape of brick, viz: the rectangular prismoidal shape shown in Figs. 14, 15, and 16, but made of a length equal to the width of two flues plus the thickness of the same brick.

Fig. 25 is a perspective view of a row of stretchers composed of. the two shapes of brick shown in Figs. 11 to 16 inclusive.

It is to be noted that in the checker-work and flues shown in the stoves in which the bricks are laid parallel to, and at right angles to a given vertical plane, there are two methods of laying the brick disclosed. rIhe first is that shown in enlarged perspective in Fig. 7. In this construction, the stretchers used are those shown in Figs. 17, 18, 19 and the fillers are those shown in Figs. 14, 15, 16. It is evident that the stretchers may be formed of brick of the shapes shown in Figs. 11, 12, 13, and 14, 15, 16, alternately placed as shown in perspective in Fig. 25, in which event the checker-work and outer wall would be composed of these two shapes of brick only. V

In the drawings, 1 is a brick of rectangular prismoidal form having both sides and endsrtapered from the wideV to the narrow base; 2, is a brick of rectangular prismoidal form having its sides tapered from the wide tion chamber; (i, the checker-work flues; 7 the supporting arches for the checker-work; and 7, the outlet to the chimney, of a side fired, hot blast stoveembodying my improvements, and having the checker-work and the wall surrounding the checker-work laid in accordance with my Patent No. 925,827 of dan. 16, 1909.

in Fig. 6, l shoiT a horizontal section of a center fired, hot blast stove in which the combustion chamber is seen at 8. The checker-work and the outer brick wall of this stove are formed of brick laid parallel to, and at right angles to a given vertical plane, also in accordance with my aforesaid Patent No. 925,827.

In Figs. 2O and 21 shown horizontal sections through a center lired, two pass, hot blast stove in which the lues and checkerwork are formed with radial and circular walls. In these iigures the combustion chamber is seen at 9 5 the flues at 10, 10a, 10D, 10C; the radial walls of the flues and checkerwork at 11; and the circular walls of the llues and checker-work at 12, 12, 12b; the wall of the center combustion chamber at 13; and the outer, solid wall of the checkerwork forming the lining of the steel shell, at 14:.

In Figs. 22 and 23 are shown horizontal sections through a center red, three pass, hot blast stove, in which the flues and checker-work are formed withradial and circular walls. ln these gures the combustion chamber is seen at 15; the second pass flues at 16, 16a, 1Gb; and the third pass flues at 17.

The construction and operation of hot blast stoves of the types shown herein are well known in the art, except as relates to my present improvements, and no further description of such stoves is here necessary.

It will be understood that the principles of my invention may be applied to other forms of regenerative stoves regardless of their design and the arts or industries in which they are used.

In Fig. 24, 2el are the rectangular prismoidal brick employed. It will be understood that successive layers of brick in this construction may be made to break joints with adjacent layers in any manner desired.

It 'will be seen that by the use of the herein described improvements greatly increased heat absorbing and radiating surfaces are eX- posed to the passing` gases, thus increasing the efliciency of the stove in which they are used and decreasing the time required to heat the checker-work. On account of the increased radiating surfaces of the saw tooth liuc walls. a `greater amount of air can be heated in a given time in a stove embodying my improvements than is possible in any stoves previously known, with which l am familiar.

By constructing the checker-work with thc'flues having their saw tooth walls pointing downward, soot, ashes, etc., cannot collect on the flue walls.

lt is to be noted that the use of my improvements permits the use of a smaller regenerator for developingl given temperature in a given time, and that, on account of the increased radiating` surface, a smaller number of stoves may be employed for supplying a constant blast of hot air than is required when stoves not enfibodying my improvements are used.

laving thus described my invention, I claim and desire to secure by Letters Patent:-

1. 1n a regenerative stove, a flue structure having vertical non-interconnecting flues therein, the inner surfaces of the walls of which fines are provided with a multiplicity of downwardly facing shoulders, each of said shoulders entirely surrounding the flue in which it is located.

2. in a regenerative stove, a flue structure, having vertical non-interconnecting lues therein, the inner surfaces of the walls of which ilues are provided with a multiplicity of projections, each having a downwardly facing horizontal surface and an upwardly facing inclined surface entirely surrounding the flue in which it is located.

3. In a regenerative stove,aliue structure having non-interconnecting flues therein, the walls of the dues being composed of brick of trapezoidal cross section built in layers one upon another, the wide bases of the brick of one layer resting upon. the narrow tops of the brick of the next lower layer, each layer of brick .being composed of spaced apart parallel rows of brick, the spaces between said parallel rows being divided at regular intervals by filler brick also of trapezoidal cross section. said filler brick having their ends beveled to rest upon the inclined sides of the brick of said parallel rows in the same layer., the rows of brick in a layer being directly superposed upon the corresponding rows of brick in the next lower layer whereby vertical non-interconnecting flues are formed extending from the bottom to the top of the structure, each of said flues, by reason of the trapezoidal shape of the brick being provided with a downwardly facing shoulder surrounding said flue at each intersection of the layers of brick of which the structure is built.

4. ln a regenerative stove, a checker-work Hue structure composed of brick of trapezoidal cross section built in layers, one upon another, the wide bases of the brick of one layer resting upon the narrow tops of the preceding` layer, each layer of brick being composed of `parallel rows of stretchers and parallel rows of fillers laid at right angles to the stretchers, the rows of stretchers and the rows of fillers being spaced apart so as to form fiues between them, the brick constituting the rows of fillers having their ends beveled to rest upon the inclined sides of the rows of stretchers.

ln a regenerative stove, a checker-work flue structure composed of brick of trapezoidal cross section built in layers, one upon another, the wide bases of the brick of one layer resting upon the narrow tops of the brick of the preceding layer, the brick being laid to form a plurality of vertical walls intersecting each other at right angles, the brick composing parallel rows in a layer having their ends beveled to rest upon the inclined sides of the brick composing` the walls running at right angles to said parallel walls in the same layer.

6. ln a regenerative stove a checker-work flue structure composed of brick of trape- Zoid al cross section built in layers, one upon another, the wide bases of the brick of one layer resting upon the narrow tops of the brick of the next preceding layer, each layer of brick being composed of parallel rows of stretchers and parallel rows of fillers laid at right angles to the stretchers, the rows of stretchers and the rows of fillers being spaced apart so as to form the said flues between them, the brick composing the rows of fillers being of rectangular prismoidal shape the end planes of which are inclined at the same angle to each other as the side planes of the stretchers are inclined to each other, whereby the fillers are supported at their ends upon. the inclined sides of the stretchers.

7. In a regenerative stove, a checkerwork flue structure composed of brick of trapezoidal cross section, built in layers, one upon another, each layer consisting of a set of spaced apart parallel rows of brick, running in one direction, and a set of spaced apart rows of brick intersecting` the said parallel rows at right angles, the brick composing one of the sets of rows being illers and having their ends beveled to conform Copies of this patent may be obtained for to the inclined sides of the brick forming the other set of rows.

8. In a regenerative stove, a flue struc ture having vertical fiues therein, the walls of the flues Vbeing composed of brick of trapezoidal cross section, built in layers, one upon another, the wide bases of the brick of one layer resting upon the narrow tops of the brick of the next lower layer, each layer being composed of two sets of spaced apart rows of brick intersecting each other at right angles to form {iues therebetween, the bottoms of the brick projecting inwardly of the iiues beyond the edges of the tops of the brick which form the next lower layer to form downwardly facing` shoulders upon the inner surfaces of the walls of the flues entirely surrounding said flues.

9. In a regenerative stove, a flue strueture having vertical flues therein, the walls of the flues being composed of brick of trapezoidal cross section, built in layers, one upon another, the wide bases of the brick of one layer resting upon the narrow tops of the brick of the next lower layer, each layer being composed of two sets of spaced apart rows of brick intersecting each other at right angles to form flues therebetween, the bottoms of the brick projecting inwardly of the flues beyond the edges of the tops of the brick which form the next lower layer to form downwardly facing shoulders upon the inner surfaces of the walls of the flues entirely surrounding said flues, and a Vsolid wall built around the checker work,

said wall being formed by filling the outer flues of the checker work with brick also of trapezoidal cross section, some ofv which are inverted so as to have their wide bases uppermost and to completely fill the said p end flues.

in testimony whereof I aiiix my signature in presence of two witnesses.

ALFRED C. NELSON.

Witnesses: Y

LUcIUs R. LANDFEAR, Dn LANCEY WV. CORLETT.

five cents each, by addressing the Commissioner of Eatents,

Washington, D. C. 

